ESPHome gives devices on unreliable Wi-Fi a better chance of completing a wireless firmware update without being carried closer to the router. The uploader switches its data transfer automatically when the connection shows packet loss, while clean connections keep the existing path.
In J. Nick Koston’s test with an ESP32 beside the uploading computer and 65% packet loss deliberately introduced in both directions, the old transfer failed every time. The new transfer completed the upload in about three and a half minutes; connection setup brought the complete process to roughly eight to twelve minutes. ESP8266 uploads also completed under the same simulated loss.
The change keeps the existing authentication and image checks, and encrypted uploads retain their encryption. Both the uploader and the device need support for the new transfer; older devices remain compatible through the ordinary method, and a blocked alternative port falls back to it.